This woman is Rochester's wife and Mason's sister, Bertha Mason. She is crazy. Rochester has kept her locked up in Thornfield watched over by Grace Poole. In chapter 25, Jane explains to Rochester how the night before, she saw a ghost in her room while she was trying to sleep. What really happened, though, was that Bertha came into Jane's room that night --the night before Jane was to be married to Mr. Rochester. Bertha was dressed in white and had a candle in her hands. Jane was sleeping, so she at first thought it wasSophie, the maid. Bertha went into Jane's closet where she found Jane's wedding dress. She took the wedding veil and put it on her own head. Then, she took the veil, tore it from her head, threw it on the ground, and stomped on it. She obviously had found out that her husband, Rochester, was going to marry Jane, without being divorced from her.

She came up close to Jane, put her candle in Jane's face, and Jane became so frightened, she fainted. She tells Rochester that she thought she had been dreaming, but then when she woke up, she found the veil on the floor, torn to pieces. Rochester tells Jane that it was Grace Poole that tore the veil, that she is weird, and it is something that she likely would have done. He tells Jane he will explain it to her more fully after they are married. Jane is terrified.

Throwing the veil on the ground was symbolic of the ruined wedding. The veil was a symbol of the marriage and by destroying the veil, Bertha destroyed the wedding because on their wedding day, Mason shows up and tells everyone that Rochester cannot marry Jane because he is already married.

We find out that Rochester married Bertha when he was very young and foolish, that her brother, Mason, tricked Rochester into marrying her without telling Rochester that his sister was half-mad already. Rochester found out the extent of her madness after they were married and rather than put her in an asylum, kept her at home with him, cared for by Grace Poole. She stabs her brother later and she is the one responsible for burning down Thornfield later in the novel.